Missions

Our team is looking for a scientific computing engineer for an 18-month fixed-term position (renewable). The successful candidate will work on modeling global methane fluxes (sources and sinks). Methane is the second most important anthropogenic greenhouse gas after carbon dioxide, but its atmospheric lifetime is much shorter (8 to 10 years). Therefore, it is a key species for short-term mitigation strategy to limit global warming. Studying the variability of different natural methane sources and sinks will help quantify their contributions to changes in global methane concentrations and to evaluate and to control the effectiveness of mitigation strategies. The main tasks of the position will involve (1) implementing and validating a simple methane emission equation for wetlands, lakes, and peatlands in the ORCHIDEE terrestrial ecosystem model, (2) producing simulations estimating methane emissions and sinks from wetlands and flooded areas, and (3) connecting the emissions produced by the ecosystem model with the LMDZ-INCA atmospheric transport and chemistry model, that is a component of the IPSL Earth System Model (ESM).

Activities

The candidate will : - incorporate the simple model of methane emissions from wetlands (SatWetCH4 1.0) developed by Bernard et al (GMD, 2024, https://doi.org/10. 5194/egusphere-2024-1331) into the ORCHIDEE terrestrial ecosystem model, - optimise this new version with on-site simulations using the ORCHIDAS optimisation tool dedicated to data assimilation (parameter optimisation), - compare the simulation results with on-site data (flux database, FLUXNET-CH4), - produce simulations of methane flows on a global scale using available maps of the distribution of wetlands (based on various satellite products), which will have to be adapted to the model format, - evaluate the simulated flows in relation to atmospheric data using the atmospheric transport model (LMDZ), - carry out simulations (as part of various projects: EYE-CLIMA, GreenFeedback, TRACCS) to estimate methane emissions from wetlands, which will be used i) for various global or regional CH4 balance summaries and ii) as a priori fluxes for atmospheric inversion models, - to adapt the tools developed for coupling ecosystem, transport and atmospheric chemistry models to methane fluxes in order to simulate the surface flux-atmospheric methane cycle interactions in the IPSL Earth system model.

Skills

- Engineering degree or PhD in environmental sciences, applied mathematics, scientific computing (or related field of physical or applied sciences), - Recommended experience or recent graduates interested in climate science and biogeochemical cycles, - Computer skills, - Interest in programming: Python for science, Shell, and possibly Fortran, - Strong interest in numerical modelling. Familiarity with at least one of the following will be appreciated: model-data comparison, process modelling, environmental physics and chemistry, data assimilation, data science, big data. - Basic knowledge of continuous integration, automatic testing and Git is a plus. - Fluency in English is required, - Fluency in French is a plus.

Work Context

The post will be based at the LSCE laboratory (https://www.lsce.ipsl.fr). This is a world-class research laboratory resulting from a collaboration between the CEA, the CNRS and the University of Versailles Saint-Quentin -UVSQ. The LSCE employs around 300 researchers, engineers and administrative staff, including many PhD and Masters students. Location: about 20 km from the heart of Paris, in the green zone of Orme des Merisiers. The post-doc will be part of the MOSAIC team and will also work with partners.

Constraints and risks

None